Michael Pinchbeck's parents met through an amateur production of The Sound of Music in Lincoln in 1970. Almost 40 years later, Michael's dad, Tony, still hasn't got over the frustration of only having one line to say: "Ulrich, block ze driveway." But the post-show party was real enough. A chap called Arthur, who had played the Baron, keeled over and died.

The death was real and so was the post-show party, but this re-creation of the party in 16 scenes (going on 17), using the soundtrack of The Sound of Music, is not, even though it features Michael and his parents. Mum played a nun in that original production, but she doesn't speak much here, except to point out that Michael and Tony have run out of ideas.

Actually she's wrong. This is a teasing, gently witty and entertaining piece about the shifting nature of reality, and it has no shortage of ideas. However, they are not always fully realised in a show in which the hills are alive with deadpan, self-conscious irony. More honesty and less clever layering would lend emotional ballast, as the people we are watching pretending to be themselves seem more elusive as every moment passes.

Perhaps there is something here in the ephemeral nature of performance and of life itself, and certainly in the way that Pinchbeck, now 60 going on 70, was younger than his son is now on that fateful night. But any wistfulness is crushed by the constant game-playing; in its current form this play is intriguing and rich with promise, but never quite beguiling.